<template>
  <div>
    <ul>
      <li v-for="(val, index) in arr" :key="index">{{ val }}</li>
    </ul>
    <button @click="btn">走一走</button>
  </div>
</template>

<script>
export default {
  data() {
    return {
      arr: ["美女", "帅哥", "程序猿"],
    };
  },
  methods: {
    btn() {
      let arr1 = this.arr.shift();
      this.arr.push(arr1);
    },
  },
};
</script>